A parking assistance device is known, which determines a movement route of a vehicle for parking positioned on a road for parallel parking. In some cases in such a device, a front end of a vehicle in the rear direction in a parking area is detected by a sensor, and a targeted parking position is set at a front side away from the front end of the vehicle in the rear direction by an avoidance distance set in advance.
JP2006-508850T (Reference 1) is an example of the related art.
However, in the device described above, in a case where the position of the vehicle in the rear direction is erroneously detected due to an error or the like of the sensor, there is a problem in that the vehicle moving along the movement route comes in contact with the vehicle in the rear direction.